The JRC – hosting the European Reference Laboratory on Food Contact Materials – contributed to a study to showing the impact of the nature of food in its "attractiveness" to contaminants from plastic packaging. The focus was on the migration of the chemical compound benzophenone from low-density polyethylene. The study revealed how specific foods and packaging polymers interact (mathematics of transfer of components from packaging into foods) to better predict migration and ultimately exposure to chemicals from food contact materials.
Packaging is essential for the production, processing, transportation and storage of foods. It protects the food against external contamination and prolongs its shelf life. Yet, polymers such as plastics that are in contact with foods during sterilisation and long life can interact with foods. Thus food contact materials and in particular plastics are regulated at EU level with strict limits imposed on any potential transfer of components that may tend to migrate into the food.
It is therefore extremely important to understand the mass transfer phenomena such as permeation, sorption and migration that may occur between polymers and different types of foods, as these fundamental aspects will dictate the potential migration of substances into the food. Various projects at EU level have generated large amounts of experimental data to develop mathematical migration models to better predict the potential migration of substances as a function of the nature of the substances, the temperature, and the type of foods.
Historically most research on modelling has focused on the on diffusion in polymers, and little was known on the specific role of the food into the physics of mass transfer. The current work exemplified using a model substance (a "migrant"), how different types of migration parameters, both kinetics and thermodynamics, are affected by the nature of the foods. The collaborative study carried out by scientists from various international organisations, including the JRC, is another step to better understand the respective role of polymers and foods in these mass transfer processes. It has also been used in a European funded project (FACET) to develop better exposure tools based on migration and food consumption to refine risk assessments and better protect the consumer.
Read more in:
J. Maiai et al.: "Determination of key diffusion and partition parameters and their use in migration modelling of benzophenone from low-density polyethylene (LDPE) into different foodstuffs", Food Add. Contam. Part A 33 (2016) 715-724 doi:10.1080/19440049.2016.1156165